Electrodeposited\nMultimetal Alloyed NiMoCo on Ni Mesh\nfor Efficient Alkaline Hydrogen Evolution Reaction

Abstract

Developing efficient electrocatalysts for industrial\nalkaline hydrogen\nevolution reaction (HER) is important for alleviating energy problems\nand achieving decarbonization. Here, a multimetal alloyed NiMoCo coating\nwas <i>in situ</i> electrodeposited on Ni mesh as an HER\nelectrocatalyst. The obtained cathode exhibits ultrahigh HER activity\nin alkaline environments, requiring only low overpotentials of 13.7\nand 146.0 mV in 1 M KOH to achieve current densities of 10 and 200\nmA cm^–2, along with a robust stability of over 120\nh at an operating current density of 400 mA cm^–2. The introduction of Co elements into NiMo-based alloys could significantly\nchange the surface morphology from a planar to a three-dimensional\nstructure for exposing abundant active sites; moreover, strong electronic\ninteraction between multimetal alloyed sites is beneficial to modulate\nalkaline HER activity. The full alkaline water splitting electrolyzer,\nwhich consisted of electrodeposited multimetal alloyed NiMoCo as the\ncathode and NiMoFe as the anode, was constructed, showing a cell voltage\nas low as 1.437 V to obtain the current density of 10 mA cm^–2 and 1.703 V for 200 mA cm^–2. This work would pave\na new avenue to design and fabricate multimetal alloyed electrocatalysts\ndirectly grown on an industrial porous conductive substrate.